1. Field of the Invention
The present invention relates to image color mapping technology. More particularly, the present invention relates to a method and apparatus for mapping colors of an image.
2. Description of Related Art
The color mapping technology can be used to apply a color transformation on final image colors. For example, when printing a document, the ink for printing the overall document or the ink for printing a certain color can be saved by performing the color transformation on the image. In addition, for an achromate, if there is a color in the image that cannot be distinguished by the achromate, the color that cannot be distinguished can be transformed into another color that can be distinguished by remapping the colors of the image, so as to assist the achromate in clearly discriminating the image.
The traditional color mapping techniques include color inversion, color replacement, color shift, etc. The color inversion means to invert a color into its inverted color. For example, black is inverted into white, and white is inverted into black. The color replacement means to replace a color with a designated color, for example, red can be replaced with yellow. The color shift means a technique which performs the color transformation by shifting three-primary color components (red, green and blue) of a color by a certain amount.
However, by use of the above color mapping techniques, display quality of the image will be significantly degraded after the colors of the image are re-mapped, thereby affecting the viewer's visual impression.